What’s in a name…


Current atmospheric change at unprecedented rates


Dutch Elfstedentocht: February 1985


476 months since any month was colder than average


Back to the race…..

How warm has is gotten?


This past July was the hottest month every recorded. July 2024 essentially tied with July 2023 has the hottest periods in modern history. July was the 14th straight month that Earth set a new warmth record for that month in both NASA and NOAA’s data, a streak that started in June 2023.

Physical impacts of climate change are visible


The September 2024 Artic sea ice minimum was 19% lower (1.1 million km2) than the past 30 year average. This was the 7th lowest recorded in satelitte era

Warming and sea ice melt might now be decoupled…..

The argument for humans as the culprit (pop’n = 8.19 billion)


Haber-Bosch process (1909) and human population



Due to its dramatic impact on the human ability to grow food, the Haber process served as the “detonator of the population explosion”

Greenhouse gases: Anthropogenic CO2 emissions trends

Global Change and Water are intimately linked



Global Change: Fresh Water Scarcity for 2/3’s of the world


Agricutural systems now require 5x more irrigation than a century ago

Global Change: Ocean acidification has multiple feedbacks


CO2 dissolving in ocean water creates carbonic acids, acidifying the oceans

Global Change: Sea Level Rise


Global Change: Humans have altered most ice-free surfaces


Global Change: New Mass Extinction?


Climate Change Resilience is Related to Affluency

Resilient countries often are responsible for more emissions


Paris Climate Agreement



  • Accord between nation in UN to address climate change


  • Goal to keep increase in global temperature below 2 °C
    • pursue efforts to limit increase to 1.5
    • pursue net zero emissions


  • Contributions by country determined by that country
    • no emissions targets or dates
    • must go beyond current efforts
    • framework for transparency

Are targets of the Paris Climate Agreement reachable?


Climate Finance Pledges ($100 million/year) are Lagging


What should we do….




  • If CO2 emissions stopped today:
    • 50% absorbed by land/water in 30 yrs
    • 30% in atmosphere for centuries
    • 20% in atmosphere for 1000 yrs


  • Future warming is inevitable
    • land sinks uncertain
    • ocean sinks weakening


  • Negative emissions technologies (carbon capture) are in start up phases